A little-noticed fight over Canadian lumber imports is a stunning example of how politics influences trade policy in Washington, say experts -- and how American consumers lose out.

The U.S. consumes some 50 billion board feet of lumber annually -- with Canada supplying roughly one-third. Included in those imports are 2x4 studs used in new home construction which have two holes drilled in them to facilitate installation of electrical wiring.

Last year, customs officials classified the studs in a way that allowed them to be sold freely across the U.S.-Canadian border at market prices. But under pressure by lawmakers from U.S. timber-producing states, Deputy Treasury Secretary Lawrence Summers successfully got customs to reclassify them. Now the drilled studs fall under quotas allowing only the first 14.7 billion board feet to be imported duty free.

• On the next 650 million board feet imported, there are fees of $50 per 1,000 board feet, and the fees double on imports beyond that.

• In 1996, the National Association of Home Builders estimated that the reclassification could add as much as $3,000 to the price of a new home -- although lumber prices have fallen somewhat since then.

• Experts say other quotas drive up the price of new homes -- for instance, textile quotas raise the price of carpets and anti-dumping duties on steel drive up the cost of pipes and tubes.

American consumers are not the only ones hurt by quotas. One lumber company executive in British Columbia says he will have to shut down production and fire about 60 workers if he cannot sell drilled studs to the U.S.